<template>
  <div class="about">
    <h1>{{ id ? '编辑': '新建' }}分类</h1>
    <el-form label-width="120px" @submit.native.prevent="save">
      <el-form-item label="上级分类">
        <el-select v-model="model.parent" placeholder="请选择">
          <el-option v-for="item of parents"
          :key="item._id"
          :label="item.name"
          :value="item._id">
          </el-option>
        </el-select>
      </el-form-item>
      <el-form-item label="名称">
        <el-input v-model="model.name" ></el-input>
      </el-form-item>
      <el-form-item>
        <el-button type="primary" native-type="submit">保存</el-button>
      </el-form-item>
    </el-form>
  </div>
</template>

<script>
export default {
  props: {
    // 这个id是拿到路由里编辑的id
    id: {}
  },
  data(){
    return {
      model: {},
      parents: []
    }
  },
  methods: {
    // 新建和编辑因为是同一个页面，所以还需要条件判断请求不同
    async save(){
      let res
      if(this.id){
        res = await this.$http.put(`rest/categories/${this.id}`, this.model)
      } else {
        res = await this.$http.post('rest/categories', this.model) 
      }
      this.$router.push('/categories/list')
      this.$message({
        type: 'success',
        message: '保存成功'
      })
    },
    async fetch() {
      const res = await this.$http.get(`/rest/categories/${this.id}`)
      this.model = res.data
    },
    // 获取上级菜单下拉框数据
    async fetchParents() {
      const res = await this.$http.get('/rest/categories')
      // console.log(res.data)
      this.parents = res.data
    }
  },
  created() {
    // 如果能拿到编辑的id 才会请求接口，将分类名称展示到页面上
    this.id && this.fetch()
    this.fetchParents()
  }
}
</script>
